Police in Colorado have launched an investigation after three revelers were shot outside a Nas gig on Thursday night. Shots rang out in the parking lot of the Red Rocks Amphitheatre, just outside of Denver, after the Feed The Rocks show featuring Nas, rapper Flying Lotus and hip-hop star Schoolboy Q. Three victims were admitted to a local hospital with non-life threatening injuries, according to Allhiphop.com, and a police investigation has been launched.